The only thing I add in my mind is that Snape cannot speak. And Harry has to check to see that the scar is there on his neck to make sure it isn't someone who looks like him.
And yeah. The rest is open for interpretation. How Snape has a child? In my mind, its a woman who saved him. *shrug*
:D I'm just floored by the reactions. Stunned... and very very happy people liked it!